this post was submitted on 03 Aug 2025
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53
Linus Torvalds on how and when to maintain a clean git history (2009) (www.mail-archive.com)
submitted 7 hours ago* (last edited 7 hours ago) by HaraldvonBlauzahn@feddit.org to c/programming@programming.dev
10 comments fedilink hide all child comments
 

I want clean history, but that really means (a) clean and (b) history.

People can (and probably should) rebase their private trees (their own work). That's a cleanup. But never other peoples code. That's a "destroy history"

So the history part is fairly easy. There's only one major rule, and one minor clarification:

  • You must never EVER destroy other peoples history. You must not rebase commits other people did.

[...]

If you are working with git together with other people, it's worth a read.

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[–] magic_lobster_party@fedia.io 10 points 4 hours ago (3 children)

I think this is dependent on context. Linus is working with a very public repository. Private repositories shared with a small team have different conditions.

What works in my smallish team at my company is:

  • Enable squash commits. Each PR should be squashed to a single commit. This makes the master branch linear and simple. This ensures each individual commit on master has been reviewed and is in a working state.
  • You can do whatever shit you want on your own branch. It’s going to be squashed anyway.
  • Don’t base your work on some other team member’s branch, unless agreed upon. That’s their work. You should only depend on the master branch.
  • Never rewrite what has already been committed to the master branch.
[–] fitgse@sh.itjust.works 2 points 1 hour ago

If ‘—first-parent’ was the default way that git log worked, I don’t think we’d even be having this argument over how to merge branches.

In my opinion, the best strategy is to always use a merge commit, and then when viewing master, always use —first-parent which will ONLY show commits on master. This gives you:

  • a very clean, linear history
  • the ability to let people work in their branches in their own way (it is ok to merge master into your branch multiple times without rebasing)
  • you can dig into the history of any branch if needed
  • it makes it easy to backport changes as you can cherry-pick out the merge commit which contains everything.

The problem is just the default log view of git and tools.

[–] wccrawford@discuss.online 3 points 1 hour ago

That sounds like pretty much exactly what we did at my last job, and it worked pretty well IMO. The individual commits in a PR didn't ever matter. I don't even think we used them for code review, except if it came up for review a second time after rework. In that case, we were able to just look at the new commit to see if the right changes were made.

And we definitely avoided basing off each other's branches. We had to do it a few times. The only times it went well was when the intent was to merge the child branch into the feature branch. If they were actually separate tickets (and the second relied on the first) it was generally chaotic. But sometimes, it was just necessary.

[–] Kissaki@programming.dev 4 points 2 hours ago (1 children)

Enable squash commits. Each PR should be squashed to a single commit. This makes the master branch linear and simple. This ensures each individual commit on master has been reviewed and is in a working state.

In non-minimal changesets, I would miss information/documentation about individual logical changes that make up the changeset. Commit separation that is useful for review will also be useful for history.

I prefer a deliberate, rebase- and rewrite-heavy workflow with a semi-linear history. The linear history remains readable, while allowing sum-of-parts changesets/merges.

It's an investment, but I think it guides into good structuring and thoughts, and whenever you look at history, you have more than a squashed potential mess.

Squash-on-merge is simpler to implement and justify, of course. Certainly much better than "never rebase, never rewrite, always merge", which I am baffled some teams have no problem doing. The history tree quickly becomes unreadable.

[–] magic_lobster_party@fedia.io 3 points 2 hours ago (1 children)

What I like with squash on merge is I don’t need to worry about shit my coworkers make. My coworkers can have terrible git disciplines, and the master branch is still clean.

[–] killeronthecorner@lemmy.world 4 points 2 hours ago

This is the reality. You'll spend most of your time working with people of varying SCM skill levels, and spread all the way across the spectrum. Squash commits combined with centralised auditing (GHE, GitLab, etc) add the necessary rail to keep a clean history on main and to make building-block change sets easily revert-able.

In my decades working on large teams of engineers, the need to identify changes by wip/interim commits has never been terribly useful for the reason you describe: everyone has different git hygiene procedures and most corps don't give a tiny little shit about maintaining that level of hygiene unless you're white room / highly regulated.

And if you do want that level of depth you can go find the PR/MR in the central source where the revision history of the dead branch is often sustained (unless you configure it not to)

But yeah, I call YAGNI a lot on git history purists to this day. It's a huge amount of effort and coordination to retain a tiny amount of value that is 50/50 gonna be useful depending on the git hygiene of the person who wrote it. Save your efforts and just read the damn code.

[–] HaraldvonBlauzahn@feddit.org 4 points 7 hours ago* (last edited 6 hours ago) (2 children)

Have you ever seen or created something like this?

This might explain why it might be useful to re-write history at all, and why tools like jujutsu or gerrit are interesting, in specific contexts.

[–] Kissaki@programming.dev 1 points 3 hours ago (1 children)

While exploring solutions, I use f or ffto mean "follow-up/to-squash" and a to mean logically separate. Sometimes other (additional) short abbreviations to know where to move, squash, and edit the changes to.

Other than maybe initial development until the first stable/usable version, these never persist, though. And even then, only if it's not a collaborative project. If it is shared or collaborative, "Iterate on x" is preferable as a non-descriptive title.

I guess my commit descriptions get better with project lifetime, not worse.

[–] Fred@programming.dev 1 points 2 hours ago

While exploring solutions, I use f or ffto mean “follow-up/to-squash” and a to mean logically separate. Sometimes other (additional) short abbreviations to know where to move, squash, and edit the changes to.

I recently discovered git commit --fixup=abcd1234: it will make a new commit with a message of fixup! <message from abcd1234>. (It's the only special thing that flag does: a specially formatted commit message, which you can craft yourself if you remember the spelling of the fixup! marker.)

When you later rebase, git rebase --interactive --autosquash will automatically mark that commit to be a fixup of abcd1234.

magit for emacs has shortcut for creating a fixup commit selecting the previous commit, I'm sure other interfaces do too.

I guess my commit descriptions get better with project lifetime

I've found that too, which I think is because as the project matures, you're more likely to make fixes or contained features, as opposed to regular "change everything" as you explore the design in a young project.

[–] Flipper@feddit.org 2 points 4 hours ago

In a project I'm in there are 20 commits just labeled .. The only reason I haven't slapped them silly is they left before I started.